Proposed Diagnostic Guidelines for Anxiety and Fear-Related Disorders in the ICD-11

Anxiety and Fear-Related Disorders are the most common of all mental and behavioural disorders across the globe and are associated with significant disability, economic costs and loss of quality of life. These disorders also often co-occur with other prevalent mental disorders and health conditions. Unfortunately, and despite the existence of highly effective treatments, these disorders are often not identified early enough, resulting in unnecessary suffering. In light of these facts, a public health classification such as the ICD-11 must assist clinicians in effectively and efficiently recognizing anxiety and fear-related disorders. Furthermore, given that anxiety is a normal emotional reaction that exists on a continuum, the classification must provide a reliable means to differentiate disorder from normality. The proposed ICD-11 classification of Anxiety and Fear-Related Disorders has been developed with these principles in mind.

In ICD-11, Anxiety and Fear-Related Disorders that manifest across the lifespan are brought together under a new grouping. Under ICD-10, most anxiety disorders are found in the grouping of Neurotic, Stress-related, and Somatoform Disorders. The proposal for ICD-11 is for all disorders with anxiety or fear as the primary clinical feature to be brought together in this new grouping. Separation Anxiety Disorder and Selective Mutism, which were classified in ICD-10 in a separate section on disorders of childhood, are also included in this new grouping. Each disorder in this grouping is defined according to its essential (i.e., required) features with a particular emphasis on the focus of apprehension, that is, the stimulus or situation that triggers the fear or anxiety. Because physiological arousal and avoidance exist in all anxiety disorders to varying degrees, the focus of apprehension provides the clearest basis for diagnostic differentiation.

Obsessive-Compulsive and Related Disorders and Disorders Specifically Associated with Stress have also been placed into their own distinct ICD-11 groupings, separate from the grouping of Anxiety and Fear-Related Disorders. The proposed ICD-11 diagnostic guidelines acknowledge commonalities among all these groupings, including the fact that fear and anxiety are often among the symptom presentations of these other disorders. Practical guidance on how to differentiate Anxiety and Fear-Related Disorders and other disorders with overlapping symptoms is provided in the proposed ICD-11 diagnostic guidelines. The ICD-11 will also cross-reference specific categories across groupings, which will help to enhance clinical utility. For example, Hypochondriasis (Health Anxiety Disorder) is a condition characterized by fear about the possibility of having one or more serious, progressive or life-threatening illnesses, and this disorder is proposed for classification among the ICD-11 grouping of Obsessive-Compulsive and Related Disorders based on several lines of research evidence. However, Hypochondriasis will be cross-referenced in the Anxiety and Fear-Related Disorders grouping.

There are several additional important changes proposed for ICD-11 classification of Anxiety and Fear-Related Disorders. First, Agoraphobia and Panic Disorder will be separate, distinct diagnosable disorders because of compelling evidence of their separate courses, incidences, gender distributions, and responses to treatment. Second, the diagnostic guidelines clarify that panic attacks can occur in the context of other Anxiety and Fear-Related Disorders, which are especially likely to be triggered by exposure to the feared stimulus or situation. In these cases, a separate diagnosis of Panic Disorder is not warranted. Instead, a “with panic attacks” qualifier is provided that can be applied when panic attacks are part of the clinical presentation of another disorder. Third, diagnostic guidelines for Generalized Anxiety Disorder are much more fully elaborated, so that it is no longer a diagnosis of exclusion. Separation Anxiety Disorder may be diagnosed in adults under the proposed diagnostic guidelines. In addition, arbitrary, non-evidenced based symptom counts or duration thresholds have been omitted from the proposed ICD-11 diagnostic guidelines in order to provide more flexibility for cultural variation and clinical judgment.

The proposed ICD-11 diagnostic guidelines for Anxiety and Fear-Related Disorders are now available for review and comment by GCP.Network members. All comments received will be considered in producing the final version of the ICD-11 diagnostic guidelines. In addition, proposed guidelines are now undergoing field testing in multiple languages via GCP.Network as well as in clinical settings around the world.